The Muffin-top Workout

It's called the muffin top—that back-of-the-hips area that bulges over the waistband of our favorite jeans. "It's body fat, plain and simple. And the fastest way to get rid of it is by doing cardio intervals," says Los Angeles trainer Valerie Waters, who works with celebs, including the notably "bloop"-less Jennifer Garner. By mixing intense bursts with slower periods, intervals torch calories faster than exercising at a steady pace. (Even better, a study found that after two weeks of interval training, women burned 36 percent more fat during moderate exercise.) Do Waters' interval plan and sculpting moves, below, three times a week to make long T-shirts an option, not a necessity.

The muffin-busting plan

These intervals work with any cardio exercise you like—such as walking, biking or jogging.

Start off with a five-minute warm-up at a low-to-moderate intensity to get your blood flowing.

Pick up the pace for one minute; the effort required should be about a 7 on a scale of 1 to 10—1 being effortless and 10 being extremely tough. Speed isn't the only way to boost intensity; try increasing the treadmill incline, running stairs or hopping onto a tough cardio machine like a stair-stepper.

Recover for one to two minutes at an easier pace—about a 5 on your toughness scale.

Repeat those hard and easy intervals for a total of 20 minutes. Once you get the interval rhythm down, throw in some spurts in which you're working at an 8 or 9 on your intensity scale to challenge your body and burn even more fat.

Cool down for five minutes at a light pace.

Check out your key moves. These exercises will tone and "cinch in" the whole area, says Waters. In other words, they devour muffins.